Cryptography can support the secure communication of information over potentially insecure communication channels. Messages to be transmitted over a communication channel can be encrypted with a key prior to transmission over the channel, and then decrypted at the receiver. Because the transmitted message is encrypted, there is reduced fear that the message will be read if it is intercepted from the communications channel before reaching the receiver. Symmetric key cryptographic systems are one example of cryptographic communications. In a symmetric key system, also known as a shared secret key system, both the transmitter and the receiver have the same secret key and that key is used to both encrypt and decrypt. Cryptographic techniques may also be used to secure stored data and in various other information and communication security applications.